Article pubs.acs.org/ac
Total Reflection X‑ray Fluorescence Analysis of Airborne Silver Nanoparticles from Fabrics Magnus Menzel and Ursula Elisabeth Adriane Fittschen* Institut für Anorganische und Angewandte Chemie, Universität Hamburg, Martin-Luther-King-Platz 6, Hamburg 20146, Germany ABSTRACT: Ag nanoparticles (NPs) are usually applied to consumer products because of their antimicrobial properties, which are desired in fabrics for sportswear as well as cloth used for cleaning. Hazards to human health from airborne Ag NPs may occur when the NPs are inhaled. NPs are comparable in size to macromolecules and viruses and able to penetrate deep into the lungs, e.g., the alveoli, where they may cause damage to cells and tissue due to their large surface area. In this study, aerosols released form fabrics treated with Ag NPs were collected using a low pressure Berner impactor and analyzed with total reflection X-ray fluorescence (TXRF). We found that the Ag NPs are released primarily in the form of larger particles, mainly 0.13−2 μm, probably attached to fiber material. Using an electron micro probe, single particles could be identified. The detection of backscattered electrons suggests small spots on the particle consist of a heavier element, which most likely is Ag, although the signal in energy-dispersive X-ray spectroscopy (EDX) was below the lower limit of detection (LOD). To achieve LODs necessary for Ag determination, Ar peaks were eliminated by a nitrogen atmosphere provided by the “Picofox-box”. This enables linear calibration and quantification of Ag. The LOD was calculated at 0.2 ng (2.0 ppb). Following the TXRF and scanning electron microscopy (SEM)/EDX analysis, the aerosol samples were dissolved in nitric acid and analyzed with ICPMS to successfully confirm the results obtained by the TXRF measurements.
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it is well-known that inhalation of nanoparticles is related to adverse health effects.9−11 While humans have been in contact with nanosized airborne particles at all times, the exposure has increased dramatically as a result of anthropogenic sources.12,13 Quadros and Marr11 reviewed the work done on laboratory scale aerosolization of mainly pure silver aerosols to simulate multiple potential aerosolization scenarios during the production, use, and disposal of consumer products treated with Ag NPs. Nonetheless, to assess the real-life human exposure, mobilization of Ag NPs directly from consumer products needs to be evaluated. Accordingly, and since harmful effects are dependent on concentrations and particle size, an extensive knowledge about the amount and size of silver nanoparticles originating from fabrics is crucial and requires a detailed analysis. In this study, (a) a polyester fabric with fused in Ag NPs and (b) a cotton fabric with Ag NPs not treated with a binder were investigated. To enhance aerosol mobilization, fabric treated with Ag NPs was abraded over 2 h using the standardized Martindale method. The Martindale procedure was developed to simulate abrasion under proper use. During this procedure, the aerosols were collected in three size fractions: 0.015−0.13, 0.13−2, and 2−16 μm using a modified low pressure Berner
ilver nanoparticles (NPs, particles with at least one dimension
